| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49513: cpufreq: governor: Use kobject release() method to free dbs_data |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| cpufreq: governor: Use kobject release() method to free dbs_data |
| |
| The struct dbs_data embeds a struct gov_attr_set and |
| the struct gov_attr_set embeds a kobject. Since every kobject must have |
| a release() method and we can't use kfree() to free it directly, |
| so introduce cpufreq_dbs_data_release() to release the dbs_data via |
| the kobject::release() method. This fixes the calltrace like below: |
| |
| ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x34 |
| WARNING: CPU: 12 PID: 810 at lib/debugobjects.c:505 debug_print_object+0xb8/0x100 |
| Modules linked in: |
| CPU: 12 PID: 810 Comm: sh Not tainted 5.16.0-next-20220120-yocto-standard+ #536 |
| Hardware name: Marvell OcteonTX CN96XX board (DT) |
| pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) |
| pc : debug_print_object+0xb8/0x100 |
| lr : debug_print_object+0xb8/0x100 |
| sp : ffff80001dfcf9a0 |
| x29: ffff80001dfcf9a0 x28: 0000000000000001 x27: ffff0001464f0000 |
| x26: 0000000000000000 x25: ffff8000090e3f00 x24: ffff80000af60210 |
| x23: ffff8000094dfb78 x22: ffff8000090e3f00 x21: ffff0001080b7118 |
| x20: ffff80000aeb2430 x19: ffff800009e8f5e0 x18: 0000000000000000 |
| x17: 0000000000000002 x16: 00004d62e58be040 x15: 013590470523aff8 |
| x14: ffff8000090e1828 x13: 0000000001359047 x12: 00000000f5257d14 |
| x11: 0000000000040591 x10: 0000000066c1ffea x9 : ffff8000080d15e0 |
| x8 : ffff80000a1765a8 x7 : 0000000000000000 x6 : 0000000000000001 |
| x5 : ffff800009e8c000 x4 : ffff800009e8c760 x3 : 0000000000000000 |
| x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0001474ed040 |
| Call trace: |
| debug_print_object+0xb8/0x100 |
| __debug_check_no_obj_freed+0x1d0/0x25c |
| debug_check_no_obj_freed+0x24/0xa0 |
| kfree+0x11c/0x440 |
| cpufreq_dbs_governor_exit+0xa8/0xac |
| cpufreq_exit_governor+0x44/0x90 |
| cpufreq_set_policy+0x29c/0x570 |
| store_scaling_governor+0x110/0x154 |
| store+0xb0/0xe0 |
| sysfs_kf_write+0x58/0x84 |
| kernfs_fop_write_iter+0x12c/0x1c0 |
| new_sync_write+0xf0/0x18c |
| vfs_write+0x1cc/0x220 |
| ksys_write+0x74/0x100 |
| __arm64_sys_write+0x28/0x3c |
| invoke_syscall.constprop.0+0x58/0xf0 |
| do_el0_svc+0x70/0x170 |
| el0_svc+0x54/0x190 |
| el0t_64_sync_handler+0xa4/0x130 |
| el0t_64_sync+0x1a0/0x1a4 |
| irq event stamp: 189006 |
| hardirqs last enabled at (189005): [<ffff8000080849d0>] finish_task_switch.isra.0+0xe0/0x2c0 |
| hardirqs last disabled at (189006): [<ffff8000090667a4>] el1_dbg+0x24/0xa0 |
| softirqs last enabled at (188966): [<ffff8000080106d0>] __do_softirq+0x4b0/0x6a0 |
| softirqs last disabled at (188957): [<ffff80000804a618>] __irq_exit_rcu+0x108/0x1a4 |
| |
| [ rjw: Because can be freed by the gov_attr_set_put() in |
| cpufreq_dbs_governor_exit() now, it is also necessary to put the |
| invocation of the governor ->exit() callback into the new |
| cpufreq_dbs_data_release() function. ] |
| |
| The Linux kernel CVE team has assigned CVE-2022-49513 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.6 with commit c4435630361d9bebf7154a0c842dc1fb7ae39c99 and fixed in 5.15.91 with commit a1964688582d26af1328e19b658933659fb54337 |
| Issue introduced in 4.6 with commit c4435630361d9bebf7154a0c842dc1fb7ae39c99 and fixed in 5.18.3 with commit 1e32083f327184b6226ce320ef30085ce785ea4e |
| Issue introduced in 4.6 with commit c4435630361d9bebf7154a0c842dc1fb7ae39c99 and fixed in 5.19 with commit a85ee6401a47ae3fc64ba506cacb3e7873823c65 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2022-49513 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/cpufreq/cpufreq_governor.c |
| drivers/cpufreq/cpufreq_governor.h |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/a1964688582d26af1328e19b658933659fb54337 |
| https://git.kernel.org/stable/c/1e32083f327184b6226ce320ef30085ce785ea4e |
| https://git.kernel.org/stable/c/a85ee6401a47ae3fc64ba506cacb3e7873823c65 |
